chem organic 6 Flashcards
(25 cards)
alkene —-> alkane
reagent, conditions, type of reaction
reagent: hydrogen
conditions: nickel catalyst
type: addition/reduction
alkene —> dihalogenoalkane
reagent, mechanism, type of reagent, type of bond fission
reagent: bromine (dissolved in organic solvent)
conditions: room temp
mechanism: electrophilic addition
type of reagent: electrophile, Br*+
type of bond fission: heterolytic
alkene —-> halogenoalkane
reagent, conditions, mechanism, type of reagent, type of bond fission?
reagent: HCl or HBr
conditions: room temp
mechanism: electrophilic addition
type of reagent: electrophile, H*+
type of bond fission: heterolytic
alkene —-> diol
reagent, conditions, type of reaction, observation?
reagent: KMnO4 in an acidified solution
conditions: room temp
type of reaction: oxidation
observation: purple colour of MnO4- ion will decolourise to coulourless
alkenes + bromine water =?
reagent, conditions, type of reaction, observation?
= alcohol!
reagent: bromine dissolved in water
conditions: room temp
type of reaction: addition
observation: orange colour of bromine water decolourises to colourless
alkene —> alcohol
reagent, conditions
hydration!
reagent: water
essential conditions: high temp of 300-600C, high pressure 70 atm, catalust of conc H3PO4 ( acid catalyst)
halogenoalkane —> alcohol
reagent, conditions, mechanism, role of reagent?
reagent: potassium (or sodium) hydroxide
conditions: in aqueous solution, heat under reflux
mechanism: nucleophilic substitution
role of reagentL nucleophile, OH-
halogenoalkane —> alkene
reagents, conditions, mechanism, role of reagent?
reagents: potassium (or sodium) hydroxide
conditions: in ethanol, heat
mechanism: elimination
role of reagent: base, OH-
what is the difference when halogenoalkane reacts in AQUEOUS sol or ETHANOLIC sol
aqueous = substitution
ethanolic/alcoholic= elimination
halogenoalkane —> amine
reagent, conditions, mechanism, type of reagent?
reagent: NH3 dissolved in ethanol
conditions: heating under pressure in a sealed tube
mechanism: nucleophilic substitution
type of reagent: nucleophile, :NH3
what cam the reaction of alcohol and sodium test for?
what are the observations?
test for alcohols.
observations: effervescence, mixture gets hot, sodium dissolves, white solid is produced
alcohol + PCl5
what does this produce?
what is this a test for and what are the observations?
produces chloroalkane, POCl3 + HCl
test for alcohols
observations: misty fumes of HCl produced
alcohol + HBr
what does this produce
Bromoalkane
how to produce HBr for the reaction to produce bromoalkane with alc?
use 50% conc H2SO4 and KBr
alcohol + PI3
what does this produce
iodoalkane
how to produce PI3
react red phosphorus and iodine
what is an oxidising agent for alcohols
potassium dichromate , K2Cr2O7
primary alcohol —> aldehyde
reagent, conditions?
reagent: potassium dichromate (VI) solution and dilute sulfuric acid
conditions: ( use a limited amount of dichromate) warm gently and DISTILL out the aldehyde as it forms
what is the observation in the reaction of primary alcohols —-> aldehydes or carboxylic acids or ketones
the orange dichromate ion (Cr2O72-) reduces to the green Cr3+ ion
primary alcohol —> carboxylic acid
reagent, conditions?
reagent: potassium dichromate (VI) sol and dilute sulfuric acid
conditions: use an excess of dichromate, and HEAT UNDER REFLUX, (distill off product after the reaction has finished
secondary alcohol —> ketone
reagent, conditions
reagent: potassium dichromate (VI) sol and dilute sulfuric acid
conditions: heat under reflux
what happens when tertiary alcohols are oxidised by potassium dichromate
THEY CANT BE OXIDISED!!
this is because there is no hydrogen atom bonded to the carbon with the OH group
how to distinguish between aldehydes and ketones
name, reagent, conditions, reaction, observation
Fehlings (Benedicts) sol
reagent: fehlings sol containing blue Cu2+ ions
conditons: heat gently
reaction: aldehydes only are oxidised by Fehlings sol to carboxylic acid and the Cu2+ ions are reduced to Copper (I) oxide
observation: aldehydes= blue Cu2+ ions in sol change to a red ptt of Cu2O
KETONES DO NOT REACT
alcohol —> alkene
reagent, conditions, role of reagent, type of reaction?
reagents: conc phosphoric acid
conditions: warm (under reflux)
role of reagent: dehydrating agent/ catalyst
type of reaction: acid catalyst elimination
